iTextSharp 字段重命名不适用于合并

这是后续另一个问题 https://stackoverflow.com/questions/44003264/itextsharp-merge-method-produces-empy-form-fields-now-duplicate-values-with-fie我之前有过，在 PDF 文件与表单字段成功合并后，如果确实出现了具有相同名称的字段，那么它们不会从原始文档中获取不同的值，看起来像具有相同名称的字段将其值传播到以下具有相同名称的字段。

这是在两个单独的函数中合并和重命名的代码：

public byte[] MergeFiles(IList<DBForms> forms)
{
    if (forms.Count < 1)
        return null;

    System.IO.MemoryStream msOutput = new System.IO.MemoryStream();
    iTextSharp.text.Document document = new iTextSharp.text.Document();
    PdfCopy copy = new PdfCopy(document, msOutput);
    copy.SetMergeFields();
    document.Open();
    List<PdfReader> readers = new List<PdfReader>();

    foreach (var docData in forms.Where(d => d.Status != 2))
    {
        PdfReader reader = new PdfReader(FlattenRenamePdfForm(docData.DocumentFile));
        readers.Add(reader);
        copy.AddDocument(reader);

    }
    document.Close();

    foreach (PdfReader reader in readers)
    {
        reader.Close();
    }

    return msOutput.ToArray();
}

private byte[] FlattenRenamePdfForm(byte[] oldDoc)
{
    PdfReader reader = new PdfReader(oldDoc);
    using (MemoryStream ms = new MemoryStream())
    {
        using (PdfStamper stamper = new PdfStamper(reader, ms))
        {
            ICollection<string> keys = stamper.AcroFields.Fields.Keys;

            List<string> keysCopy = new List<string>();

            foreach (var key in keys)
            {
                keysCopy.Add(key);
            }

            foreach (var key in keysCopy)
            {
                stamper.AcroFields.SetFieldProperty(key, "setfflags", PdfFormField.FF_READ_ONLY, null);
                stamper.AcroFields.RenameField(key, String.Format("{0}{1}", key, new Guid()));

            }

            stamper.Close();
        }
        reader.Close();
        return ms.ToArray();
    }
}

这是在使用最新的iTextSharp库5.5.10时完成的，测试是在w8Ben文档上完成的

这是文件

First

Second

Merged